About 300 people — nature lovers, college professors, old friends — gathered Sunday in downtown San Diego to pay tribute to the late hiker and writer Jerry Schad.

That the weather was October perfect — a clear sky, a light, cool wind — seemed fitting, said those who attended the afternoon memorial and had known the longtime outdoorsman. He died last month at the age of 61.

“Wow. Look at this day,” said family friend Francie Sanders told the crowd, assembled on a large patio at the El Cortez Hotel. “This is a Jerry Schad kind of day.”

Schad, who moved downtown a few years ago after residing in East County for decades, is perhaps best known for his nature photos and writings. He penned the longtime best-seller, “Afoot & Afield in San Diego County,” an exhaustive guide to trails.

Friends, family and others also remembered him Sunday for his decades as a physical sciences professor at San Diego Mesa College and City College.

They remembered him for his tight bond with those around him and his whirlwind love affair and marriage with Peg Reiter. They married in March.

And they remembered him for his clear-eyed acceptance of death after he learned earlier this year that he had final-stage kidney cancer. He even wrote a letter to be read at the memorial, months before his Sept. 22 passing.

“He was unbelievable,” said Stan Marder, a former Mesa College colleague.

In his letter, Schad wrote about his love of nature and his family, and about finding true love late in life with Reiter and savoring it.

“I had never believed in the concept of soul mates,” he wrote. “But I was wrong.”

His three sisters spoke at the memorial, along with several friends. His wife sat in the front row.

On their first date, in early 2010, Schad and Reiter hiked the west side of Balboa Park, on a stretch known as Trail 43. Schad was active with the Friends of Balboa Park and helped establish the trail system that crosses the park.